Cameras have been and continue to be critical components in both motion picture and television feature production. An important criterion for the use of a camera in television or motion picture capture tasks is the ability to smoothly follow an action item, such as an athlete, with the camera. However, cameras usable in motion picture and television work are typically heavy and cumbersome to manipulate. For example, a standard television camera may weigh 100 pounds or more. Thus, in order for a camera to be manipulable so as to provide such smooth operation, it is desirable to balance the weight and inertia of the camera and to mitigate the effects of minor unintended forces on the camera by the operator.
In order to stabilize the motion of a camera on a camera head, it is typical to employ drag mechanisms. One such prior art drag mechanism is illustrated in U.S. Pat. No. 4,955,568 (“the '568 patent”) to O'Connor et al, entitled “Panhead For Camera,” which is assigned to the assignee of the present invention and is hereby incorporated by reference in its entirety for all that it teaches. In particular, the '568 patent illustrates an adjustable fluid drag mechanism. It is useful for camera operators to have ready access to data describing the various drag settings for the camera, so as to accurately adjust such settings and to be able to accurately reproduce a desired setting at a later time. However, the mechanism illustrated in the '568 patent does not provide for the rapid collection and display of measurement data relating to the drag forces set by the operator. Other prior art mechanisms have also not provided integral mechanisms for sensing drag settings and quickly conveying such settings to the camera operator in a unified way. Rather, prior art techniques have generally employed visual mechanical mechanisms that do not provide the level of accuracy, repeatability, and ease of use desirable in the motion picture industry.
Generally, counterbalance measures have been utilized to balance the weight of the camera about the tilt axis. An example of a spring-operated counterbalance technique is described in the '568 patent, previously incorporated by reference in its entirety. Other counterbalance techniques have been employed as well. For example, counterbalances using linear springs or cam and roller architectures have sometimes been employed.
However, prior art counterbalance techniques generally function well only for small to medium tilt angles. While the counterbalance mechanism disclosed in the '568 patent functions over a tilt angle of ±90° and desirably exerts a sinusoidal restoring torque, none of the prior art techniques, including that of the mechanism disclosed in the '568 patent, are adapted and ideally suited for heavier cameras. Many of the cameras in use today for motion picture and television filming work, however, may far exceed 200 pounds in weight. For that reason, a heavy-duty counterbalance mechanism adapted to accommodate the counterbalance loads produced by such equipment is needed.
Additionally, prior art mechanisms for attaching a camera or other equipment unit to a camera head are not suitable for use with heavy equipment. That is, they do not provide sufficient ease of attachment and detachment for cameras that are cumbersome due to extreme weight. For example, a typical sliding dovetail connection requires a user to slide a heavy object along a precise axis while holding the object level until support is achieved. Even systems that permit one side of the dovetail base to drop away for camera removal still require manual intervention by the user to force the dropping side down.
In addition, it is often desirable for a camera operator or film editor to know the position of the camera throughout a shot or sequence in order to reproduce a scene or to coordinate special effects with the actual footage taken. The prior art, however, has not included means by which the camera operator could readily ascertain and thereby reproduce the exact position of the tripod and camera.
Accordingly, it is a general object of the invention to provide an improved camera panhead that smoothly pans and tilts while allowing instantaneous capture and display of camera position and drag setting information. A more specific object is to provide a head that provides the instantaneous electronic capture and display of the camera position and movement.
It is a further object of the invention to provide an improved camera panhead that is able to provide nonlinear counterbalance action for heavy cameras or other equipment throughout a wide range of tilt angles.
It is a further object of the invention to provide a camera head that allows easy and accurate adjustment of the counterbalance and drag settings.
It is a further object of the invention to provide an improved camera head that allows for the natural and uncomplicated mounting and removal of heavy cameras or other equipment to the panhead.